15 Year vs 30 Year Mortgage Calculator
Compare monthly payments and total interest for 15-year, 30-year, and extended-term mortgages.
Purchase Information
Purchase price of the home.
Percentage of the home price paid upfront in cash.
Interest Rates
Annual percentage rate (APR) for a 15-year mortgage.
Annual percentage rate (APR) for a 30-year mortgage.
Annual percentage rate (APR) for an extended-term mortgage.
Derived Purchase Values
Total cash paid upfront based on your down payment percentage.
Mortgage principal after subtracting the down payment.
Term Comparisons
15 Year Mortgage
Principal and interest payment per month.
Total interest paid over the full loan term.
30 Year Mortgage
Principal and interest payment per month.
Total interest paid over the full loan term.
50 Year Mortgage
Principal and interest payment per month.
Total interest paid over the full loan term.
Interest Savings
Total interest saved by choosing a 15-year mortgage instead of a 30-year mortgage.
Total interest saved by choosing a 15-year mortgage instead of an extended-term mortgage.
Total interest saved by choosing a 30-year mortgage instead of an extended-term mortgage.
About this calculator
This calculator compares monthly payments and total interest costs across different mortgage terms, including 15-year, 30-year, and extended-term mortgages.
It helps you understand how loan length affects affordability today versus total interest paid over time.
What each input means
- Home price – Purchase price of the home.
- Down payment – Cash paid upfront, expressed as a percentage of the home price.
- Mortgage rates – Annual percentage rates (APR) for each loan term being compared.
How this calculator works
The calculator applies the standard mortgage amortization formula to compute monthly payments and total interest for each loan term.
It assumes the same home price and down payment across all scenarios, isolating the impact of loan length and interest rate on total cost.
Factors that affect Results
- Loan term length – Longer terms reduce monthly payments but increase total interest.
- Interest rates – Even small rate differences can significantly change lifetime interest costs.
- Down payment size – Larger down payments reduce loan balances and interest paid.
- Affordability constraints – Lower payments may improve cash flow but increase long-term cost.
Key assumptions & limitations
- Fixed-rate loans – Rates are assumed constant for the entire loan term.
- Principal & interest only – Taxes, insurance, PMI, and HOA fees are excluded.
- No refinancing – Assumes the loan is held for the full term.
- Estimates only – Results are illustrative and not financial advice.